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ID 17097
file
creator
Itoh, Kuniharu
Kawano, Akio
Saito, Ko
subject
formic acid
thermal decomposition
bifurcation reaction
IRC
reaction-path Hamiltonian
NDC
Chemistry
abstract
Transition state structures, activation energies, and the intrinsic reaction coordinate (IRC) for the two decomposition paths of formic acid are studied using Hartree-Fock and density functional theory (DFT). Formic acid decomposes via the following competing paths; to: (1) H2O+CO and to (2) H2+CO2. Experimental results which were obtained by Saito et al. have shown that the rate constant of path (2) is smaller than that of path (1) by about forty times over the experimental temperature range. On the other hand, calculated results using high level ab initio calculations such as MP4/cc-pVQZ//B3LYP/cc-pVTZ show that the activation energies of paths (1) and (2) are comparable. Detailed examinations of the mode coupling between the vibrational modes and the IRC's suggest that the large difference in the rate constants between the two reaction paths is attributable to the difference in curvature of the potential energy surfaces for the reaction paths around the IRC.
journal title
Journal of Molecular Structure : THEOCHEM
volume
Volume 545
issue
Issue 1
start page
197
end page
205
date of issued
2001-07-09
publisher
Elsevier
issn
0166-1280
ncid
publisher doi
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
author
rights
Copyright (c) 2001 Elsevier Ltd.
relation is version of URL
http://dx.doi.org/10.1016/S0166-1280(01)00406-7
department
Graduate School of Science